I would suggest trying to replicate the problem connecting by ip address only. If you can't reproduce the symptoms the culprit would likely point at DNS or WINS.
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jmreichaJun 20 '12 at 13:19

I'm embarrassed to admit that I got this problem, then realized I hadn't clicked the "apply" button after "Allow users to connect remotely to this computer" had been checked...after I did then it worked.
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rogerdpackDec 19 '14 at 13:41

Just ran into this today. The problem was actually a very simple one: the credentials that Remote Desktop was using automatically were for a different computer, and it was automatically being rejected.

So, for example, I had just connected to ComputerA as Administrator, so Remote Desktop tried to sign into ComputerB as ComputerA/Administrator, not ComputerB/Administrator. Changing the sign-in name fixed it immediately.

FYI i would not recommend saving your remote desktop credentials if you can help it. All it takes is for someone to grab your RDP file and they will be able to login to whatever computers you are saving credentials for. Also, I think the error message is quite different if you try to login to a server using credentials that dont match up with the server you are trying to connect to.
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Richie086Dec 13 '13 at 20:41